Fluid-pressure brake.



NQ 8579911. PATENTE@ SUM 25 man W, V. TURNER a; B H. `BLMJKALL,

PLUME PRESSURE BRAKE. zaEI-LI'UATIOTH FILED SEPHLZB, 1903.

Aff f UNTTED STATES PATENT orrioa.

WVALTER V. TURNER, OF WILKINSBURG, AND ROBERT H. BLAOKALL, OF EDGEWOODPARK, PENNSYLVANIA, ASSIGNORS TO'THE VVESTING-- HOUSE AIR BRAKE COMPANYOF CORPORATION OF PENNSYLVANIA.

FLUID-PRESSURE BRAKE.

Specification of Letters Patent.

Patented June 25,1907.

Application filed september 26,1903. serial No. 174,710.

To a/ZZ whom it' may concern.'

Be it known that we, IVALTER V. TURNER of Oct. 30, 1906.

In the operation of trains down long grades, it is necessary to hold thebrakes applied for comparatively lonfr periods, during which time thepressure lea is away more or less from the brake-cylinder, and, as iswell known by those familiar with the present standard automatic airbrake apparatus,

.this condition of things necessitates further and often repeatedreductions of train pipe pressure for the purpose of supplying the brakecylinder lfrom the 'auxiliary reservoir to compensate for such leakageand keep up suiiicient pressur@ in the brake cylinder to safely controlthe speed of the train. This continued drain upon the auxiliary`reservoir often causes a depletion of the pressure therein to such apoint that it becomes necessary to release the brakes in order .torecharge the auxiliary reservoirs, which is a very dangerous. condition,since the train may gain such supply`of fluid tothe brakecylinder while'45' sov headway during the time of recharging with brakesreleased as toget beyond control. According tothe above mentioned prior patent 834,342these difficulties are overcomel by providing a valve device operated bythe opposing pressures of a maintaining chamber and the brake cylinderfor controlling the the brakes remain applied and thereb f compensatefor the leakage, the release o fluid from said maintaining chamber beingcontrolled by the triple valve device.

The object of our present invention is tov provide a valve meansoperativelyseparate from the triple valve forreleasing iiurd from themaintainingjchamber and also from the brake cylinder when the train pipepressure is increased for the purpose of releasing the brakes, wherebythis fluid will be discharged even though the triple valve should stickor, for any reason fail to move to release position at that tin1e.

In the accompanying drawing, Figurefl shows diagrammatically a standardcar equipment of air brake apparatus with our,

improvement applied thereto; andFig. 2

' shows a central sectional view of one form of our improved valvedevice upon a larger4 scale.

The usual standard ,air brake equipment as applied to cars comprises thetrain pipe 1, having branch pipe 2, connected to the triple rITTsBURe,PENNSYLVANIA A\\ valve device 3, auxiliary reservoir 4, and-4 brakecylinder 5. According to' said prior" patent the construction comprisesa valve device 6, connected to thetrain pipe by pipe 7, and to the brakecylinderby pipe 8. The

casing of the device contains the two chambers 10 and llseparated by themovable diaphragm 12 havin a stem 13, whichvoperates the valve'14 orcontrolling the equalizing passage or port 30 around the diaphragm fromthe brake cylinder chamber 11 to the maintaining chamber 10, and 'isalso arranged to engage the stein 17 of the regulating valve 18 which isnormally held closed by the spring 19 and controls the supply ofairunder pressure from the train pipe and pipe 7 to the chamber 11 andthroughfpipe 8 to the brake cylinder. A check valve '20 is located inthe pipe 7 to prevent a return flow fromthe brake cylinder. to .thetrain pipe lin case of'an emergency application of the brakes, due to abursted hose or other accident.

A light spring 16, and washer 15, maybe used for returning the diaphragm12 and its. stem 13 to normal position,` as shown, when the pressures inthe two chambers are equal,

and the Washeris preferably arranged to rest but according to ourpresent improvement a separate valve device' is provided for this purepose. A preferred form of such device mayA 24ior releasing thecompressed air from the 'chamber 10 to the atmosphere When dia- Iplnfagmis moved forward under an'increase of train pipe pressure, a lightsprin@ 28 being employed for normally holding the valve in positionshown With the port 25 closed.

The operation. ofthe device is as followsza 'When a reduction in trainpipe pressure is Triade in theA usual Way for applying the brakes the.diaphragm 21 remains in position shown, since its stem acts as a stopagainst the casing,I and consequently the port 25 revmains closed, atthe same time air under pressure 4from the brake cylinder enters chamber1'1 through pipe 8 and raising diaphragm 1`2 opens .valve 14 andequalizes through passage 3() into the maintaining chamber 10. Thediaphragm then returns under pressure of spring 16 to its normal poysition, thus closing valve 14 and sealing up the air. in chamber 1Qatprecisely the same degree` of pressure as that of the brake cyliirder. If,'now, the brakes are heldapplied for ysome time and thebrakecylinder pressure is diminished from leakage, the constantpressureof chamber. 10 Will cause a depression of 'fthe ,diaphragm 12and valve 18 so as to suply a sufficient amount of air under pressure omthe train pipe Kto the brake cylinder to compensate for such leakage andmaintain the braire cylinder ressure constant and 'equal to that heldsea ed up in chamber 10, it beingunderstpod that any desirable means may`be empll ,yed for supplying iiuid to the train pipe. hen the train pi epressure is increasedfor releasing the bra es the triple valve moves torelease position in the usual Wayfor dischi Y"ging the brake cylinder tothe atmosphere., and at the same time the increased pressure in chamber29 operates to move the diaphragm 2'1 and valve 26 to establishcommunication between ports 25 and 24 and thus release the compressedair from chamber 10 to vthe atmosphere.

If Jfor any reason the triple valve should stick and fail to release thebrake, the air discharging from the chamber 10 would permit the raisingoil the diaphragm 12 and valve 14 to open the port 30, through which thebrake .cylinder' pressure would then be released to the atmospherethrough chamber 1() and ports 25 and 24. In this Way the/necessity ofbleeding the auxiliary reservoir andbrake cylinder in the case of a,defective triple valve is avoided. p v

By means oitbis construction, it will new plied for any desired lengthof time and the bra-ke cylinder pressure constantly maintained at anydesired degree without further depleting the auxiliary reservoirs ornecessitating the release of the brakes for the purpose oi rechargingsaid reservoirs. It will also be seen that the improved device isentirely independent-rin its action and may be applied directly to thepresent standard automatic-air brake system Without 'changing thestructure or .interfering in any Way 'with the operation. of any oi' theparts of said system.

Having now described our invention, what We claim as new and desire tosecure by Letters i atent is 1. In a iluid pressure brake, thecombination with a train pipe, auxiliary reservoir, triple valve andbrake cylinder, of a valve device operated by the pressure in amaintaining chamber for controlling the supply of iiuid to the brakecyiinder While the bralres are applied, and means voperated by'anincrease in train pipe pressure for releasing uid from said chamber.

Z. In a iiuid pressure brake, the combina` tion with a train pipe,auxiliary reservoir, triple valve and brake cylinder, or' a valve deviceoperated by the pressure in a maintaining chamber for controlling thesupply of fluid to the brake cylinder While the brakes are applied, andmeans operated by an increase in train pipe pressure independent of themovement of the triple valve for releasing fluid from said chamber and,from the brake cylinder.

3. In a 'liuid pressure brake, the combination With a train pipe,auxiliary reservoir, triple valve, and brake cylinder, of a valve devicehaving a diaphragm subject to the opposing pressures of the brakecylinder and a `Huid pressure chamber forcontrolling the supply of fluidto the brake cylinder While the brakes are applied, and means operatedby an increase of train pipe pressure for releasing the iiuid from saidchamber.

4. In a iiuid pressure brake,tlie combination With a train pipe,auxiliary reservoir, triple valve, and brake cylinder, of a maintainingchamber having apdiaphraginwexposed to brake cylinder lessuref a' valveoperated by the diaphragm for controlling the supply of iiuid to thebrake cylinder, and means operated by the train pipe and auzgil-'f iaryreservoir pressures for releasing the iiuid from the maintainingchamber.

5. In a iiuid pressiire brake, the combination With a train pipe,auxiliary reservoir, triple valve, and brake cylinder, of a maintainingchamber, means subject to the opposing pressures of the maintainingchamber" andthe brake cylinder for controlling the supply of iuid fromthe IJtia'in pipe to the-brake cylinder, and means operated by anincrease of train pipe pressure for releasing {ie-'apparent that. thebrakes may belheldaps' the fluid inem the maintaining chamber.

IOO

IIO

@imma in e 'Fluid pressiiie bmiie, the Combina tieii Wit tie-iii pipe,auxiliary ieseivei", giipie Valve, mid bleke eyiiiider, of a, veive foreonieiiing the supply of Huid te the iiieiie cjyiiiideiwviiie thebi'akes are applied, means ,Subjeet te the eppiising pressures ef bebrake ey ii :uni e constant pressure im opei'ating seid Valve, and meansopera-mii by @n @i iwim'ii pipe piessuie for ieg seid Constantpies'ezire.

.in a, iuid pressuie brake, die eeziibilia- 'ien with n, t-iiii pipe,auxiliary leeerveir, tiipie Vaive, and bia-ile cylinder, of el.mainiiiiig ehfiiiibeii, means Subjeet to iiie ep- ,eemig pieesuies e?mid ehembei" and the niieiie eyliiideir foi eentioiiiiig lie suppiy efi'viifi ie ffie brake eyiiiider, :ind vaive de- Opeieited. "irjr theepi/)ming piessui'es of 'i *fr .A .i pipe iii-d: the au' jg? reservoirfoi 1 die .5r-.iii iiei'ii die iiiziiiif-iniiig eiiambei.

e. in e. 'Huid pessuie brake, the combina.- tieli Widi a iziiin .,ipmauxiliary reservoir, tipie Valve. @mi brake cylinder, of a meintaiiiiiigChamber, means subject te the p- (if seid eiiiiibei and the iiiiiei" im'eeixtioiiiiig the suppiy ef :Live device epeiaeii by an iiieieaee ofifi'aiii 9. in a fluid pressure bre-ke, 'the eoiiibiimtion 'fitfii atrain pipe, auxiliary ieseivoi, triple vmive, sind brake eyiinde7 ei e.,mein-- taining; chamber hmiiig a. Teive eentoiied equaliziiig passageeeiiiiiiimieetiiig with 'The brake ej'iiiider, mea-ns O'Geiied bythe 0ipo ing pressures of said. eheiiibei and. the brake eyiiiide fueeeiitreiiiiig iie Suppij; of fluid te the emke e Bilder, and a. 'waivedevice operated 'by mi iiierease el? im-iii pipe pressuie im ieieiisiiigthe iuidiom said Chamber.

1G. in i 'Huid pressure brake, tie eeiiibiiiation with i train pipe,:wxiiii j. ieseiveir, tripie valve, and brake cylinder, of e maintainingehzmibeif, 'means Subject te the opposing pressures 0i." said.eliaiiiieei and the brake cylinder foi eeiiioiiiiig iie suppiy of 'Huidthe brake ejyfiiiidei, ineens foi charging said eimiibei Wih pi theesirei brake eyiiiiciei pi mure, i ieiezise valve fo? said chamber,ei'id. a di piiiagm subject te die Opposing pressures of the tein pipeand the auxiiiaiy ieseivoii for @penitingg saie felee-sevaive iiitestimony whereof We have hereunto Sei our bends. i

YVALTER V. TURNER. ROBERT H. BLACKALL.

'f'vitiiessesz E. F. EMERY. JAS. E. MAeDoNALQ.

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